附件公司
US ˙ NasdaqGS ˙ US03589W1027

SecurityANNX / Annexon, Inc.
InstitutionMorgan Stanley
Latest Disclosed Ownership2,735,970 shares
Latest Disclosed Value $ 15,157,274
Morgan Stanley reports 4.21% decrease in ownership of ANNX / Annexon, Inc.

On May 15, 2026 - Morgan Stanley filed a 13F-HR form disclosing ownership of 2,735,970 shares of Annexon, Inc. (US:ANNX) valued at $15,157,274 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on May 27, 2026 disclosing 2,856,143 shares of Annexon, Inc.. This represents a change in shares of -4.21% during the quarter. The current value of the position is $14,911,036 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F ANNEXON COM 03589W102 2,735,970 -120,173 -4.21 15,157 5.72 0.0009
2026-05-27 2025-12-31 13F/A-1 ANNEXON COM 03589W102 2,856,143 -173,705 -5.73 14,338 55.15 0.0009
2026-02-13 2025-12-31 13F ANNEXON COM 03589W102 2,856,143 -173,705 14,338 0.0009
2026-05-27 2025-09-30 13F/A-1 ANNEXON COM 03589W102 3,029,848 2,197,308 263.93 9,241 362.51 0.0006
2025-11-14 2025-09-30 13F ANNEXON COM 03589W102 3,029,848 2,197,308 9,241 0.0006
2025-08-15 2025-06-30 13F ANNEXON COM 03589W102 832,540 131,184 18.70 1,998 47.67 0.0001
2025-05-15 2025-03-31 13F ANNEXON COM 03589W102 701,356 56,679 8.79 1,354 -59.09 0.0001
2025-05-15 2024-12-31 13F/A-1 ANNEXON COM 03589W102 644,677 -590,808 -47.82 3,307 -54.79 0.0002
2025-02-14 2024-12-31 13F ANNEXON COM 03589W102 644,677 -590,808 3,307 0.0002
2025-05-14 2024-09-30 13F/A-2 ANNEXON COM 03589W102 1,235,485 227,071 22.52 7,314 48.03 0.0005
2025-02-14 2024-09-30 13F/A-1 ANNEXON COM 03589W102 1,235,485 227,071 7,314 0.0005
2024-11-14 2024-09-30 13F ANNEXON COM 03589W102 1,235,485 227,071 7,314 0.0001
2025-05-14 2024-06-30 13F/A-2 ANNEXON COM 03589W102 1,008,414 108,901 12.11 4,941 -23.38 0.0004
2024-10-17 2024-06-30 13F/A-1 ANNEXON COM 03589W102 1,008,414 108,901 4,941 0.0004
2024-08-14 2024-06-30 13F ANNEXON COM 03589W102 1,008,414 108,901 4,941 0.0004
2024-10-17 2024-03-31 13F/A-2 ANNEXON COM 03589W102 899,513 707,453 368.35 6,450 640.41 0.0005
2024-08-16 2024-03-31 13F/A-1 ANNEXON COM 03589W102 899,513 707,453 6,450 0.0001
2024-05-15 2024-03-31 13F ANNEXON COM 03589W102 899,513 707,453 6,450 0.0005
2024-08-16 2023-12-31 13F/A-1 ANNEXON COM 03589W102 192,060 42,968 28.82 872 148.15 0.0001
2024-02-13 2023-12-31 13F ANNEXON COM 03589W102 192,060 42,968 872 0.0001
2023-11-15 2023-09-30 13F ANNEXON COM 03589W102 149,092 41,755 38.90 352 -6.90 0.0000
2023-08-14 2023-06-30 13F ANNEXON COM 03589W102 107,337 -30,767 -22.28 378 -29.00 0.0000
2023-05-15 2023-03-31 13F ANNEXON COM 03589W102 138,104 53,133 62.53 532 20.96 0.0001
2023-02-14 2022-12-31 13F ANNEXON COM 03589W102 84,971 30,026 54.65 439 29.12 0.0000
2022-11-14 2022-09-30 13F ANNEXON COM 03589W102 54,945 -57,210 -51.01 340 -19.43 0.0000
2022-10-27 2022-06-30 13F/A-1 ANNEXON COM 03589W102 112,155 -156,167 -58.20 422 -42.35 0.0001
2022-08-15 2022-06-30 13F ANNEXON COM 03589W102 112,155 -156,167 422 0.0000
2022-10-27 2022-03-31 13F/A-1 ANNEXON COM 03589W102 268,322 -31,975 -10.65 732 -78.78 0.0001
2022-05-13 2022-03-31 13F ANNEXON COM 03589W102 268,322 -31,975 732 0.0001
2022-02-14 2021-12-31 13F ANNEXON COM 03589W102 300,297 247,677 470.69 3,450 252.40 0.0004
2021-11-15 2021-09-30 13F ANNEXON COM 03589W102 52,620 -44,034 -45.56 979 -54.99 0.0001
2021-08-23 2021-06-30 13F/A-1 ANNEXON COM 03589W102 96,654 61,709 176.59 2,175 123.54 0.0003
2021-08-16 2021-06-30 13F ANNEXON COM 03589W102 96,654 61,709 2,175 0.0001
2021-05-17 2021-03-31 13F ANNEXON COM 03589W102 34,945 -6,775 -16.24 973 -6.89 0.0001
2021-02-16 2020-12-31 13F ANNEXON COM 03589W102 41,720 39,227 1,573.49 1,045 1,293.33 0.0002
2020-11-13 2020-09-30 13F ANNEXON COM 03589W102 2,493 2,493 75 0.0000
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.